The primer becomes jammed down and does not return to its original (up) position. When it's jammed down, air is drawn into the pump, making it VERY noisy and doesn't work very much. There are no details on how to disassemble the primer to gain access to the inside, where the issue lies. (Removing the primer is easy, just 8 screws.) Getting the primer's button out of its casing is where I need extra help. Apart from this primer issue, it's a great filter.

Very good build quality, runs quiet, primes well, can't recomend enough

Couldn't wait for the New Filter to arrive fast postage nicely packed.Very happy with this product nice and Solid highly reccommened Aqua One Aquis 1250 Series II Canister Filter thank you so much and the price was exceptional

Aqua One Aquis 1250 Series II Canister Filter is good value for money compared with other brands.Plus, its quiet, energy efficient & powerful pressurized filter is easy to set-up and operate. The quick release tap system ensures fast and mess-free filter maintenance. The primer button makes priming a cinch! The filter substrate consists of balls of sintered glass; but with its capacious, modular design, I could "pimp it up" with 'Biohome Ultimate' media distributed by the Genesis Group (I watched "The Pond Guru's" video review of the canister on YouTube)... Upgrading the biological media and re-arranging the mechanical filtration with 3 layers of sponges (coarse to fine in the bottom tray) improves its efficiency and helps lower Nitrate levels as the biological media enables both aerobic and anaerobic bacteria activity - thus reducing the need to do water changes every 2-3 days in my community tank - love it!

Excellent quality filter. Comes with everything you need to set up your tank. Delivered on time at a price that cannot be beaten. One very happy customer.

Very well built and great quality setup. Easy to use. Works brilliantly. Would definitely recommend this to others.